Dental model articulator



Oct. 1937. R. A. PITTMAN ET AL 2,094,903

DENTAL MODEL ARTICULATOR Filed Nov. 4, 1935 2 Sheets-Sheet l .Tn l ffil'af F4 1 J06? ar/761' 9% W Oct. 5, 1937. R. A. PITTMAN ET AL DENTAL MODEL ARTICULATOR Filed Nov. 4, 1955 7 2 Sheets-Sheet 2 .ZM/vm a? f yes- -P Patented Oct. 5, 1937 UNITED STATES PATENT FFEQE DENTAL MODEL ARTICULATOR Application November 4, 1935, Serial No. 48,144

2 Claims.

This invention relates to improvements in a device for holding molds in which models of portions of the human teeth and jaws may be cast and after the casting of such models they may be articulated.

It particularly relates to an articulatorfrom which the models may be removed in order that they may be worked on or reproduced and in which the models themselves or reproductions thereof may again be secured, and removed as often as it may thereafter be found necessary.

The invention also relates to means by which the parts of the articulator may be relatively adjusted in order to provide desired positioning of the mold with reference to the articulator and to provide such other adjustments of the parts as may be necessary or desired to properly position them during the model casting operation, and thereafter to properly articulate the models themselves.

The primary object of the invention is to provide a model holder in which the models are directly mounted in such manner that either or both may be removed and replaced, such number of times as may be desired without the removal with the models of any part of the holder itself.

A further object of the invention is to provide a model holder in which one of the holder parts may be shifted laterally with regard to the other thereof to provide proper articulation of the models.

A further object is to provide a simple and effective mold holder which may be readily adjusted vertically and which also may be tilted out of horizontal to align the mold.

The means by which the foregoing and other objects are accomplished and the manner of their accomplishment, will readily be understood from the following specification on reference to the accompanying drawings, in which,

Fig. 1 is a side elevation of the articulator with a mold and models therein. 7

Fig. 2 is a plan view of the articulator with mold and models removed.

Fig. 3 is a section taken on the line III-III of Fig. 2.

Fig. 4 is a section taken on the line IVIV of Fig. 1, and

line VII-VII of Fig. 9, showing a slightly modified form of the device with the mold in place.

Fig. 8 is a corresponding end elevation.

Fig. 9 is a plan view.

Fig. 10 is a sectional plan taken on the line IX IX of Fig. 7 with the mold removed.

Referring now to the drawings in 'which the various parts are indicated by numerals, H] is an upper holder and H a lower holder. From the lower holder a pair of arms l2 extend upwardly and rearwardly and are provided at their upper ends with bosses l3. I4 is a plate which lies between the bosses I 3 and is pivotally secured thereto by screws [5, which preferably are thumb screws having knurled heads, and having coned points which enter complementary recesses in the ends of the plate M to provide pivotal engagement. The rear end portion l6 of the upper holder Ii] overlies the plate l4 and is oscillatably secured thereto by a clamping screw I1 and thumb nut I8. Secured in the portion [6 of the holder I0,-are pins l9 which are laterally displaced from the screw ll, these pins extending into arcuate grooves 20 in the-plate l4 and cooperating therewith to limit the oscillation of the holder. The forward portions of the upper holder ll]. and the lower holder l I, are each formed by two prongs 2|, 22 which are spaced apart throughout their length and which have opposed inner edges or faces which converge rearwardly. In cross section these inner edges of the upper prongs are bevelled, forming downwardly converging faces whereas the inner edges of the lower prongs which are also bevelled, converge upwardly. The upper holder I0 is provided with an opening 23 separated from the inner ends of the prongs by a bar 24 through which opening a suitable tool may be inserted to exert a prying action on the back end of a model held by the prongs and thereby to eifect the disengagement of such model. The lower holder ll may be provided with a similar opening should it be so desired.

In Fig. 6 a modified form of upper holder is shown in which a single central prong HA is substituted for the two prongs of the preceding figures, the outer edges of this prong diverging rearwardly and being'bevelled, these bevels diverging downwardly in order to hold a model thereon. The lower holder may of course be similar.

Extending upward from the lower holder H approximately at the junction of the part l2 therewith, is a slotted post 25 against which a post mold retainer 26 is secured as by a screw 21 and a nut 28, the nut 28 preferably having an elongated body and a knurled portion 29 usable of the slot, it being. understood however that in engaging and disengaging it. The retainer the pin may be moved out of engagement with 26 has oppositely disposed prongs 30, 3| which this central depression by, turning pressure of are adapted to lie on. opposite sides of a, mold. the member 59. The upper holder 50 is provided which is to be held.- thereby. The retainer is at its rear end with two arms each having a ordinarily positioned asshownin Fig. 5 with its boss H through which screws 12 extend to proprongs' 30, 3| horizontally opposite. It may be videpivotal engagement of the holder arms with raised or lowered by loosening the nut 28 and the member 59;

slidingit upward or downward in the slot'in the The holders 50 and 5| as before, are provided 10 post 25. ,Also the prongs may be rocked about with prongs 1'3, 14, respectively, 'l iaving inner the screw, 27 'as an axis to raise or lower one faces which converge rearwardl'y and'are shaped prong relative to the'other thereof and thereby in cross section as before. The converging faces be adapted to receive a distorted or twisted mold o f these arms are preferably stepped apart toward 7 and hold it in aparticular position or :aligntheir outer =ends, shoulders 15, 16 being formed ment, or to adjust such alignment. 32 is a at the junction of the two face se'ctions'against screw preferably having a knurled head-which 4? which the model is formed and against which it screw is threaded through the upper holder l0 abuts whenbeing replaced after removal. These '7 and which projects below-this holder into enshouldersperform in this respect the same funcgagement with the upper end of the post 25. tion for a transversely disposed model that the i -20 33 is ajamb nuton the screw 32. ThefSClGW bottom 110f the slot performs for a longitudi- 32 forms a support for supporting the :upper nally disposed model,.or.that the shoulders 'lflpf' holder in with respect-to the lower, holder. l-l Fig. .6 perform. 7 I 7 and provides means'ior adjusting the relative Theouter ends of the'prongs 13 are joinedby positioning thereof. The mold which is of usual a transverse bar 89 which carries at its center type ordinarily comprises. a bite-tray formed a hollow boss 6| through which is slidably dis'- of two. spaced side members-34, which members posed a post-.82, this post being adjustably-secu-red ordinarily are made of this comparatively stifi by-a set screw 83. The 'outer .end of the lower pasteboard and are secured together adjacent prongs. .are joined 'to and carrya transverse their horizontal mid-portionsby a diaphragm -of plate 84 having an inclined. upper face .85 on 9 strong cloth'35 ordinarilysecured to the 'paper which the lower end of the post.82 rests. The" sides by stitching. 36, 31 are respectively the upper holder may also be tapped-toward the rear upper and lower wax mold portions which. are end, but forward of the .bolt .58, to receive an 7 retained bythe side members 34 and separated adjusting screw 90, .thelowerendof which screw 7 by the cloth-diaphragm 35. 38 and 39 are rerests on aninclinedportion 9-1 of the lower holder. spectively the upper and lower models which The screw 99 andthepost-82 perform essentially are ,formed in the' waxj'portions 36, 31- of the the same service and it will be understood that mold and which models are removably held by one or the other may be .omitted. Ordinarily'the the holders l0 and II. post support .is not :used with the illustrated nare a In Figs. 7 to :10 inclusive, is the upper. holder rower type of holders, but is used only with the 1 Q and 5| the lower holder, the rear end of which well known Gysi articulator type patented ;Octol lower holder is bent upward to form a slotted 'ber 15, 1912, No. 1,041,270 and .isintroduced *for 53 having a 't forward end oppositely 'extendapost.

a threaded sleeve 55, thence through the slotted. Figsrl to 5 may be used with this :type of-holder ,post 52'and' being clamped to the 'jpostnby a 1 if a longitudinally disposed mold is to be supknurled nut 56.. RQgted.

,52, as nay be desired; that the :rod may be 7 tray. .This is then placed in the-mouth and the raised and lowered'and-clamped at desired height teeth .are claznped down displacing the waxiu-riti=l in-the slotted post andimay be turned abontgits the teeth-meet as in biting, except that the cloth' the fingers 54. At its upper end the post :52 is displaced forms anexact mold of v the teethand a 0. therefrom. .On this bolt is turnably mounted about three-minutes. Thereafter the --mouth is nutu-fillgand lock nut :61'; 'The "horizontal portion between the prongs .of the retainer and secured 5 82 which is:pro vided wi-th 'a deeper depression with the mold secured ,in place isthen placed 63 in-a-lignment with the longitudinal axis of in the model holdenand is adjusted upward .or

out to provide a recess :64 'in which is disposed position relativelyto the top and bottom'model pin 66, having a rounded end, downward, this erly align with the holder above and below, the

p by the downward pressure of the spring and beabout the-screw 21"as an axis, to secure 'such ing :adapted .to engage :the ends of this {slot to alignment and thereafter the clamping nut 28 be a additionally to engage the-(center, depression :63 therein in .proper position.

1 post 5.2, this slotted post aadjustably; carrying a the purpose of showing a closed end holder -of;

Mg which includes a threaded rod this type applicable toian articulator havingsuch;

ing fingers '54, the ds extending through-:a [It will be understood that the retainer-26" j. It will 'be particularly noted'that-xthe sleeve -In usingthe devicetwo pieces of suitably pre- 0-.55'may'be adjusted along the rod :53 to advance pared tough wax rare softened by heating and-are g the fingers 5'4 further from'or closer to' the :post placed in the upper and lower sections of the-bite 5 longitudinaliaxis. to regulate the "positioning of diaphragm separates them. The softened-wax so p bent horizontally to form a continuation or 'porthe gumsther-eabover The teeth are held closed tion '51. 1-58 is a--.bolt securedji-n the horizontal long enoughto allow vthe wax-to cool an dharden portion 51 :and extending vertically upward sufficiently .to hold its shape, requiring usually almember ,59 which member ,is' adapted to. be opened :and the mold removed, the above being. clamped against thehorizontal portion .5lby ;a usual practice. The mold so formed: is placed 7 I 51 has in its upper surface an arcuate groove thereto by an easily melted wax 40.. The retainer thelowerholder. The member *59 is chambered downward along the slotted .post 25to adjust its a .pompression' spring which acts {to push a holder; Should the mold so positioned not prop- 'pin beingheld in engagement with the slot 62 retainer may "be tilted to one'side or the other.

I vlimitvturning zmovem'ent :of the member .59 and tightened to secure the retainer with the mold The same procedure is followed with respect to the form of the device shown in Figs. '7 to 10 if a retainer having forked prongs is used. However, if the retainer 53, 54 is used, it should ordinarily be adjusted longitudinally also.

With the mold secured, an investment material such as a specially prepared plaster of Paris or some other of the harder setting materials which are purchasable for this purpose is then mixed to a plastic consistency and the upper mold filled, care being taken that the investment material accurately fills the mold; that the upper portion thereof firmly engages the opposite prongs of the model holder, and against an end 11 or shoulder portion ?5 thereof, and that it extends level with, or preferably slightly above the tops of the prongs. When the upper model has set sufficiently to permit, the holder is inverted and the operation repeated for the lower model. After the two models have thoroughly set and hardened a tool may be inserted as in the opening 23 and the models gently dislodged from the prongs of the upper and lower holders. This may be done with the wax mold still in place, or if preferred, the upper holder may be raised with its model and the then accessible mold be removed. In any event the models after very light jarring may be removed from their respective holders and afterwards may be restored therein at any time it should be so desired. When the models have been removed from the holders they may be trimmed up in such manner as may be desired and any desired modifications or changes be made. It will readily be seen that a model may be shifted longitudinally even though the end of the holder be closed as by the bar if space be left as in Fig. 'l, and when so shifted may be moved downward from the holder when so shifted.

When completed both models are, or either model is turned over to the laboratory to make bridges, plates or the like, as may be desired, and provided the laboratories are equipped with a corresponding articulator, are if and when desired, assembled in such articulator. When the laboratory has completed its work, the models and the completed Work are returned to the dentist who may then reassemble the models in his own articulator and do such other work thereon as occasion may require. In such replacement the shoulders 15, 16 or the bottoms 11, 18 of the holders prevent undue wedging of the models in the converging jaws.

It often happens that it is desirable to displace one holder of the articulator laterally with respect to the other. Such displacement may be effected by loosening the thumb nut l8, and

' after the shift is accomplished retightening it.

replacing the models in the holders to slightly shift one holder and the model carried thereby with respect to the other holder and its model to make a perfect articulation of the teeth of the two models, and this may likewise be done by loosening and tightening the thumb nut 18.

The thumb screws 32 or or the adjustable post 82, are used primarily in establishing the relative spacing of the upper and lower holders before making the model and after the models are made may be retracted allowing one model to seat on the other, unless one model only is being used.

It is understood that articulators are made to which the model is permanently attached for its life and that articulators are also made havin removable parts to which the models are attached. In the first of these cases an articulator must be retired from other use until the model has served its purpose and is destroyed and that the same is true of the removable parts of articulators in which such parts are made a part of the model. These latter also are subject to lessand are a constant source of trouble. However the primary advantage of the present device is that models once made may be indefinitely preserved and be at any time available for reuse.

What we claim is:

1. In an articulator for dental models, upper and lower model holders spaced and held apart, and a slotted post adjacent an end of said holders carried by one thereof and projecting toward the other thereof; a mold holder comprising a round, elongated member having prong portions adapted to be engaged with and support a mold for said models, said member being disposed through said slot, and being threaded throughout a major portion of its length, a nut disposed on said threaded portion forming an adjustable abutment adapted to contact one side of said post and a second nut on said threaded portion adapted to clamp said post against said abutment.

2. In an articulator for dental models, an upper model holder and a lower model holder spaced and held apart, said holders each comprising a body portion having prong members extending forwardly therefrom, said prongs having forwardly diverging model engaging surfaces, said body portions each being apertured. rearwardly but adjacent the rear ends of said prongs, whereby to permit insertion through said aperture of a model disengaging tool and exertion on said model of a prying strain to disengage said model, said body at the rear edge of said aperture forming an abutment adapted to act as a tool fulcrum.

RALPH A. PITTMAN. JOSEPH A. GARDNER. 

